Problem: Convert $\dfrac{21}{2}$ to a mixed number.
Solution: First, divide the numerator by the denominator. $21 \div 2 = {10}\ \text{ R } {1}$ So the improper fraction has $10$ wholes in it, which is equal to ${10} \times \dfrac{2}{2} = {\dfrac{20}{2}}$ This quotient $10$ is the whole number part of the mixed number. We also have a remainder of $1$ , though. That represents the $\dfrac{{1}}{2}$ remaining from the improper fraction; it wasn't enough to be another whole number. The converted mixed fraction is ${10}\ {\dfrac{1}{2}}.$ Note that if we add up the two pieces of our mixed fraction, ${\dfrac{20}{2}} + {\dfrac{1}{2}}$, we get the original improper fraction $\dfrac{21}{2}$.